Can I use Vancouver tap water with semi-hydro?

[spinrah]

Originally Posted by Ray

1. I have no idea why folks think RO is necessary for S/H growing. If your water is OK for traditional culture, it’s fine for S/H. Sure, purer is better, but that’s universal.
2. The average pH level is probably fine, as-is. 5.5-6.5 is what I shoot for, but +/- a full unit is still OK.
3. The applied solution pH is far less important than what happens in the pot. Before you go making adjustments, do this:
   • Water the plant thoroughly with your plain water.
   • Wait 30 minutes to let it drain thoroughly and chemically equilibrate.
   • Trickle about 50 ml of PURE water over the medium and collect the drainage.
   • Test the pH of that.
   • Repeat using your fertilizer solution. It probably won’t be a whole lot different.
4. Be wary of “pH Down” products. Most are phosphoric acid, and there have been examples of long-term phytotoxicity with its continued use.

Great, thank you. I was wondering whether the media inside the pot also affects the pH, so your method makes a lot of sense.